Method of switching cutting knife arrangements

#1. Field of the Invention

#This invention relates to a method of switching arrangements of cutting knives to change the slitting width in a slitter for slitting a wide sheet into a plurality of narrow strips by a plurality of cutting knives arranged at predetermined intervals, and more particularly to a method of switching arrangements of such cutting knives which can easily attend to requirement toward an additional arrangement of the cutting knives.

#2. Description of the Related Art

#FIG. 1 is a schematic side view showing an example of slitter to which the method of the present invention is applied,

#FIG. 2 is a schematic front view showing a part of the slitter,

#FIG. 3 is a view for illustrating procedure of switching arrangement of cutting knives in accordance with a method a first embodiment of the present invention,

#A method of switching the arrangements of cutting knives in accordance with a first embodiment of the present invention will be described, hereinbelow. The method of the present invention is applied to, for instance, a slitter shown in FIGS. 1 and 2. In FIGS. 1 and 2, a slitter comprises a pair of pass rollers 1 and 5 around which a wide sheet H in a continuous length such as raw web of photographic paper is passed, a feeding means (not shown) for feeding the wide sheet H in the direction of arrow A in FIG. 1, upper and lower shafts 2U and 2L which extend substantially normal to the feeding direction of the wide sheet H respectively above and below thereof, a plurality of upper and lower knife holders 3U and 3L (e.g., seven each) respectively mounted on the upper and lower shafts 2U and 2L to be movable along the shafts, and a plurality of upper and lower knives 4U and 4L respectively mounted on the upper and lower knife holders 3U and 3L.

#A lower knife moving mechanism 6L is disposed below the lower shafts 2L to be movable up and down in the direction of arrow B. The upper shaft 2U is rotated by a rotating mechanism (not shown) in the direction of arrow D between a cutting position shown by the solid line in FIG. 1 and a retracted position shown by the broken line. An upper knife moving mechanism 6U is disposed above the retracted position of the upper shaft 2U to be movable up and down in the direction of arrow C.

#The lower knife moving mechanism 6L is fitted on a guide shaft 7L, extending in parallel the upper and lower shafts 2U and 2L, to be slidable along the guide shaft 7L. The lower knife moving mechanism 6L is in mesh with a threaded-shaft 9L and is slid back and forth along the guide shaft 7L in response to rotation of a motor 8L. Similarly the upper knife moving mechanism 6U is fitted on a guide shaft 7U, extending in parallel the upper and lower shafts 2U and 2L, to be slidable along the guide shaft 7U and at the same time is in mesh with a threaded shaft 9U and is slid back and forth along the guide shaft 7U in response to rotation of a motor 8U. In FIG. 2, the guide shafts 7U and 7L are omitted.